Remember that dream you had where you superimposed your face on Christina’s hair/corset/fishnets/stripper heels and when you opened your mouth her voice came out?

Yeah, well, Hayden actually got to live that out IRL when she took on “Lady Marmalade” on the genius Lip Sync Battle — AND THEN THE REAL CHRISTINA AGUILERA JOINED HER.

(That part was so good/unexpected it didn’t even happen in our dream.)

Co-host Chrissy Teigan is super adorable in her black feather boa — yep, we all owned one of them circa 2001 — and lost her sh*t when Christina emerged from behind a wall of feathered fans and topless male dancers.

As you do. Tiny Hayden — she’s only 5 ft — absolutely slayed the Moulin Rouge tune in a red corset costume, and massive blonde ‘fro wig that Xtina dreams are made of.

Actually, are we we allowed to call Moulin-Rouge-era Christina “X-tina”? Or does that name only apply to Dirrrty-yellow-buttless-chaps-era X-tina?